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A196945
Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,1,0,2,3 for x=0,1,2,3,4
1
4, 38, 210, 1416, 9199, 60206, 393585, 2575161, 16853437, 110272832, 721534069, 4721192123, 30892105126, 202135973690, 1322631911588, 8654346869839, 56627813612708, 370531619063820, 2424491930970999, 15864128119739556
OFFSET
1,1
COMMENTS
Every 0 is next to 0 4's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 2's, every 4 is next to 4 3's
Column 3 of A196950
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +17*a(n-2) +54*a(n-3) +140*a(n-4) +336*a(n-5) +294*a(n-6) -1373*a(n-7) -2487*a(n-8) -2527*a(n-9) -8223*a(n-10) -17899*a(n-11) -17316*a(n-12) -5640*a(n-13) -11863*a(n-14) -31770*a(n-15) -22665*a(n-16) +9130*a(n-17) +27976*a(n-18) +12809*a(n-19) +7193*a(n-20) +3395*a(n-21) +7688*a(n-22) -2355*a(n-23) +476*a(n-24) -420*a(n-25) +47*a(n-26) -115*a(n-27) +30*a(n-28) -5*a(n-29) for n>31
EXAMPLE
Some solutions for n=4
..1..2..0....0..2..0....0..1..0....0..2..0....0..0..2....1..1..0....0..1..1
..1..0..2....0..2..0....0..1..0....0..1..0....1..1..0....0..0..2....0..0..0
..0..1..1....2..1..1....0..0..1....2..1..0....0..2..0....0..1..1....1..1..2
..0..0..0....0..0..0....0..2..1....0..2..0....0..2..0....2..0..0....0..2..0
CROSSREFS
Sequence in context: A245129 A196851 A196702 * A240287 A092642 A020865
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 08 2011
STATUS
approved